Door lock



NOV 5 1957 H. D. SQUIRE 2,812,204

DOOR LUCK Filed Feb. 14, 1955 1N VEN TOR. HERBERT n. JQa/EE U HISATTORNEY United States Patent O DOOR LOCK Herbert D. Squire, Galesburg,Ill., assignor to Midwest Vll/Ianufacturing Corporation, Galesburg,Ill., a corporation of Illinois Application February 14, 1.955, SerialNo. 487,838

6 Claims. (Cl. 292-334) This invention relates to spring door latchesand more particularly to a latch of the class which holds the doorsecurely in a closed position and which, upon opening the door, iscocked so that when it is closed it is automatically released tosecurely hold the door closed.

Under certain conditions it is desirable to provide a door which is heldin a closed position by a spring latch and wherein such latch, duringthe opening, is automatically cocked so htat it may be closed with arelatively small effort. Such latches are particularly useful inconnection with the doors for closing the openings in refrigerratorlcabinets.

Although a great many latches have been provided to perform thisfunction they are usually of a relatively large and complicatedconstruction. As a matter of fact, they are so large that in certainplaces, such as the inner doorsof refrigerators, their use isprohibited. By my present invention I have provided a latch mechanismwhich embodies a minimum number of operating parts and which may be maderelatively small as compared with the prior art and still provides ampleholding power for the purpose for which they are intended.

Another disadvantage of the prior latches resides in the fact thatthe'mechanism employed required a door of considerable thickness due tothe combinations of complicated springs and levers. The latch of thepresent invention may be used on relatively thin doors which isparticularly desirable when the door happens to be a door closinglafreezing locker inside of a refrigerator.

In the drawings:

Pig.. l, is a'medial sectional View through a latch mechanism and aportion of a door to which it is attached, and showing-a portion of astrike mechanism in position; f Fig. 2, is a similar view showing theposition taken by theiparts when the door is being opened;

l.i Fig. 3,A is a view showing the position the parts take i 'after thedoor has been opened and the handle released;

Fig. 4, is a View taken from therline 4--4 of Fig. l; Fig. v5, is a planview of the latch removed from the assembly; n

Fig. 6, is a side elevational View thereof; Figs. 7y and 8 are plan andside elevational views of a spring used for operating the same; and YyFigs'. 9 and l0 are plan and side elevational views of a spring for usein a latch of the in- `ing means for holding the bolt in an openpositionand operable upon closing the door to release the bolt so that itholdsrthe door closed. The Vdoor is illustrated at lbzand `is preferablyprovided with a recess yat 11 shaped to re- `ceive'the latch proper sothat the handle may bel substantially ush with the surface 12 of theYdoor.

jip-The. latch vproper includes a rectangular housing 15 which is.provided `witha Apair of bosses l@ into which screws 17 may be threadedafter passing through openings in the door to hold the housing securelyto the door. The housing is preferably made of a die cast metal andtherefore may be cored in various manners in the interest of savingmaterial. Functionally, however, it is provided with guideways for thereception of the bolt which comprise bosses 18 spaced from the open edgeand bosses 19 at the rear edge, the inner faces of the bosses being inalinment to provide a channel therebetween in which the bolt is slidablydisposed. At the rear corners of the housing there are providedrectangular anges 20, and, at the front, L-shaped flanges 21 for thereception of a keeper plate 22. This plate is seated between the flangesand also abuts the lugs at the rear 23 holding the parts in place andprotecting the assembled mechanism from contact with the door.

As previously stated, the bolt is slidable in the guideways describedthrough the open front edge 25. The bolt includes a striker engagingportion 30 and is slidably disposed in the guideways. As viewed in Fig.l, the upper side of the bolt is provided with a recess 32 ofrectangular formation, one end of which is closed by a wall 33 and theother end 34 of which is open.

A helical spring 35 engages with the wall 33 and with an abutment 36 onthe rear of the housing and pushes the bolt outwardly. Opposite to therecess 32 the bolt is provided with a boss 40 which rides on a surface41 of the housing, the forward section of the boss being undercut at 42.This undercut portion extends transversely completely across the boss,as can best be seen in Fig. 5.

Forwardly of the wall 33 the bolt is provided with a rectangular opening4S, the limits of which are defined by the strike engaging portion 30and the wall 33. This opening is adapted to receive a tongue 47 of theoperating lever or handle 48 which is pivotally supported on a pin 49,which pin is journaled in bosses 50 on the outer corners of the housing.

As can be seen from the figures, the spring 35 urges the bolt outward,the limits of the outward movement being determined by the perpendicularsurface 52 on the projection 47. When the handle 48 is swung about thepivot 49 the bolt is forced rearwardly against the pressure of thespring 35.

Astrike is provided and includes a holding surface 56 and a cam surface57. In the position shown in Fig. 1, the bolt is engaged with thesurface 56 which is inclined at a more acute angle than the surface 57and since the pressure of the spring`35 upon the bolt is in an outwarddirection, the angle of this surface is such as to hold the door tightlyclosed. When it is desired to open the door the handle is grasped by theoperating end 48 and rotated to the position shown in Fig.y 2, whereinthe bolt is retracted by the arm or tongue 47 against the lpressure ofthe spring 35. The bolt may be retracted sufficiently for it to be outof contact with the apex of the strike so that the door may be openedfreely without the bolt touching the strike when the handle is in theposition shown in Fig. 2.

As previously stated, it is desirable in a device yof this character toprovide `a latch Where the bolt is operated by spring means in such amanner that its action, together with the strike, holds the doorresiliently closed. Preferably, means should also be supplied whereby,when the door is opened, the bolt is moved to a cocked position where itremains while the door is open, but, is released by engagement with thestrike upon closing the door to reinstate the effect of the originalspring holding means.

In the present invention, the foregoing isV effected by the use of aspring which performs the dual functionl of moving the handle to aclosed position and whichL operates as a sear in conjunction with thebolt to hold it in the cocked position.

The spring, as best shown in Figs. 7 and 8, and comprises a U-shapedbody having the side arms 60 the ends at one end being connected by abight 61. The arms 60 each connect to an enlarged helical spring-portion 62 comprised of three loops forming the helix andlthencontinues` by a short arm 63 to a single loop helix 64, one end of whichterminates in a stub arm 65. It will be appreciated that if the stubs 65are held and the arms 60 moved, that the greatest bending will occur inthe larger loop 62 and the less bending in the loop 64 because the loops62 are more resilient than the smaller loops 64. The loops 64 aredisposed about the pivot pin 49 with the arms 65 engaging a slantingsurface 66 on the handle 48. The larger loops 62 extend alongside thelatch, as can best be seen in Fig. 4, and the bight 61 extends oppositeto the latch surface defined by the boss 40 and opposite to the springrecess 42.`

The walls 18, vthe inner surfaces of which guide the bolt, are providedwith notches 67 in which the arms 60 of the spring engage, the point ofengagement being close to the loops 62.

In the closed position, as shown in Fig. l, the arms 60 bear against thebottoms of the notches 67 in the walls 18 and the helices 64 aredisposed around the pivot pin 49 with the arms 65 engaging the abutmenton the handle to retain the handle closed. In this position, as can bestbe seen in Fig. l, the bight extend-s under the latch out Of contacttherewith. At Ythis time the spring 61--65 is merely holding the handlein its closed position. The coil spring 35 isholding the latch in thedoor holding position against the striker surface 56.

When the handle is moved to the position shown in Fig. 2, the arm 47 ofthe handle moves the bolt backwards, compressing the spring 35, and thesurface 66 on the handle rotates the short stub arm 65 about the pivot49. This causes the parts 63 to rotate. yAs previously pointed out, thehelices 62 bend easier than the helices `64. Therefore, since the arms60 are supported by their engagement with abutments 18 there is apivotal action of the arms 60 at these` abutments permitted by theresiliency of the helices Y62 of the spring. Therefore, the portion 61of the spring moves upward against the` bottom side 41 of the bolt.Actually this movement would first cause the bight 61 to engage thesurface 41, as can be seen from the position it is in, in Fig. l, andcontinued movement of the handle would cause the bight 61 of the springto slide across the surface and finally snap down to the position shownin Fig. 2 opposite to the undercut 42. As previously stated, the latchis now out of engagement with the striker and the door may be opened.Immediately upon release of the handle the spring 35 pushes the boltoutward and the bight 61 engages with the undercut surface 42 of thebolt and holds the bolt against further movement outward. The spring 65however returns the handle back to the normally closed position, theparts taking the position shown in Fig. 3. The parts are now in thecocked position.

When the door is closed, which would be in a direction towards the camsurface 57 of the strike, this cam surface having a lesser degree ofslant than the stop surface 56, relatively small closing pressure uponthe door will cause the bolt to be pushed inward against the pressure ofthe spring 35 and when the door reaches the apex of the strike theinward movement of thebolt is sufficient to cause the undercut portionor sear 42 to release the bight 61 of the spring. The handle being inthe position shown in Figs. l and 3, the spring 35 now takes over andsince the bolt is on the side 56 the door is held securely closed.

Ifit should be desirable to provide a lock which does not have thiscooking feature all that is necessary is to replace the spring shown bya spring having the single helix 64 and without the helices 62, whichIspring is shown in Fig. 9.

Preferably, the bolt is made of nylon or other suitable plasticmaterial. It will thus be seen that I have provided lil 4 a latch whichperforms all of the advantages previously described, which is simple andeconomical to manufacture.

Having thus described my invention and embodiments thereof it will beyappreciated that the embodiment described is for the purpose ofillustration rather than of limitation, and that numerous and extensivedepartures may be made therefrom without departing from the spirit orscope of the invention as `defined in the appended claims.

I claim:

l. A latch mechanism comprising a bolt, means for slidably holding saidbolt and for transferring its holding effort to a door, a handlepivotally connected to the holding means and having a lever armengageable with said bolt for moving the bolt, spring means engaging thebolt and holding means and moving the bolt outward of the holding means,a second spring means having a portion for engagement with the pivot forthe handleand a portion in engagement with the handle for holding the'handle resiliently in a closed position, said second spring means havingan extension and a portion between the pivot engaging portion and theextension of greater resiliency than the other portions, a second pivoton said bolt holding means for pivotally supporting said extensionadjacent the portion of greater resiliency and a spring engaging portionon said bolt for interlocking engagement with said spring extension.

2. A latch mechanism comprising a bolt, means for slidably holding saidbolt and for transferring its holding effort to a door, a handlepivotally connected to the holding means and having a lever armengageable with said bolt for moving the bolt, spring means engaging thebolt and holding means and moving the bolt outward of the holding means,a second spring means having a portion for engagement with the pivot forthe handle and a portion in engagement with the handle for holding thehandle resiliently in a retracted position, said second spring meanshaving an extension andv a portion between the pivot engaging portionand the extension of greater resiliency than the other portions, asecond pivot on said bolt holding means for pivotally supporting saidextension adjacent the portion of greater resiliency and a springengaging portion on said bolt for interlocking engagement with saidspring extension, said second spring means being formed to normally holdthe extension out of contact with the bolt and being bendable about theportion of greater resiliency to tilt the extension into engagement withthe bolt,.and means for moving the bolt after closing the door torelease said second spring means.

3. A latch mechanism for a door comprising a housing, a bolt, saidhousing being formed with spaced aligned abutments for receiving thebolt slidably therebetween, said bolt being formed with a pocket whichislopen at one end and a spring disposed in said pocket with one endengaging the bolt and the other end engaging the housing for slidablymoving the bolt outwardly of the housing, a strike engaging outerportion on said bolt, a movable operating handle for said bolt, pivot.means pivotally connecting the handle to said housing opposite thestrike engaging portion ofthe bolt, said handle having a lever and saidbolt being provided with an opening and said lever being disposed insaid opening and holding the bolt in the housing against the pressure ofsaid spring and movable to move Vthe bolt inward of the housing, aspring means for holding said lever in a retracted position including apair of small loop portions disposed on opposite sides of the boltsurrounding said pivot means, said spring means vbeing formed with shortarms extending from said loops engaged with said lever at surfacesthereon which provide seats for said short arms, said spring means beingformed Vwith portions extending away from said loops in oppositedirection to saidy short arms and having enlarged loops which provideportions of greater resiliency than the small loops disposed alongsidesaid bolt adjacent the small loops and long arms extending from saidlarge loops, one pair of said abutments being provided with notches forproviding a second pivot for said long arms, said long arms being seatedin said notches and -extending beyond said abutments opposite to saidbolt, said bolt being formed with an undercut shoulder, and said longarms being formed with a connecting bight for engagement with theshoulder, the short arm of said spring means extending from the smallloop at an angle relative to the portion connecting the small loop tothe large loop of substantially 90 and the long arm extending from thelarge loop at an angle relative to the connecting portion of less than180, said seats for the short arms and for the long arms beingpositioned so that in the handle retracted position the bight of saidspring means is normally out of contact with the bolt, said spring meansbeing bendable at the large loops to pivot the long arms on said secondpivot and move the bight into engagement with said undercut shoulderonthe bolt, the bolt being movable into engagement with the bight andsaid bight holding said bolt against further movement by saidrstmentioned spring, the bolt being movable to a bight releasingposition upon engagement of its outer strike engaging portion with astrike.

4. A latch mechanism for a door comprising a housing, a bolt, saidhousing being formed with guideways for receiving the bolt slidablytherebetween, a spring for said bolt engaging the bolt and the housingfor slidably moving the bolt outwardly of the housing, a strike engagingouter portion on said bolt, an operating handle for said bolt, pivotmeans for connecting the handle pivotally to said housing, said handlehaving a lever disposed in holding engagement with the bolt against thepressure of said spring, said handle movable to move the bolt inward ofthe housing, a spring means for holding said lever in a latched closedposition including a pair of small loops disposed on said pivot means,said lever being formed with spring engaging surfaces forming seats forsaid spring means and said spring means being formed with a pair ofshort arms extending from said small loops engaged with the lever atsaid surfaces, said spring means being formed with arms extending awayfrom said small loops in opposite direction to said short arms andconnected to enlarged loops which provide portions of greater resiliencythan the small loops disposed alongside said bolt, means on said housingproviding a second pivot for said spring means, said spring means beingformed with a pair of long arms seated on said second pivot andextending away from said large loops beyond said guideways opposite tosaid bolt, said bolt being formed with an undercut shoulder, and saidspring means being formed with a bight interconnecting said long armsfor engagement with the shoulder, the short arms of said spring meansextending from the small loops at an angle relative to the armsconnecting the small loops to the large loops of substantially and thelong arms extending from the large loops 5 at an angle relative to theconnecting arms of less than said seats for the short arms and for thelong arms being positioned so that in the handle retracted position thebight of said spring means is normally out of contact with the bolt,said spring means being bendable at the large loops to pivot the longarms on said second pivot and move the bight into engagement with thebolt, said undercut portion of the bolt being movable into engagementwith the bight and said bight holding said bolt against further movementby said rst-mentioned spring, the bolt being movable to a bightreleasing position upon engagement of its outer strike engaging portionwith a strike.

5. A latch mechanism comprising a locking member movable betweenretracted and extended positions, means resliently biasing said lockingmember to its extended position, a manually actuated operating membermovable from `a rst position to a second position to retract saidlocking member against the urging of said biasing means, and a singlespring biasing said operating member to its iirst position and actuatedin response to the manual actuation of said operating member to saidsecond position to engage the retracted locking member and maintain thesame retracted, said spring while maintaining the locking memberretracted also returning the operating member to its rst position whenthe operating member is manually released.

6. A latch mechanism comprising a housing, a bolt slidable in saidhousing between retracted and extended positions, rst spring meansacting between the housing and the bolt to bias the bolt to its extendedposition, an operating lever pivotally mounted on the housing formovement from a rst position in which it extends alongside of thehousing to a second position in which it projects out from the housing,said lever having a portion positioned to engage the bolt and retractthe bolt against the bias of said rst spring means upon movement of thelever from said first position to said second position, and secondspring means acting on the lever to bias the lever to said iirstposition, said second spring means having a portion engageable with thebolt which is actuated in response to movement of the lever from saidfirst position to said second position to engage the retracted bolt andmaintain the bolt retracted, said first spring means maintaining theretracted bolt in engagement with said portion of the second springmeans, and said second means, upon return of the lever from said secondposition to said first position and movement of the bolt further againstthe bias of said first spring means, moving out of the path of the boltto permit the bolt to move to its extended position.

References Cited in the file of this patent UNITED STATES PATENTS537,055 Mandell Apr. 9, 1895 621,600 Caldwell Mar. 21, 1899 1,301,326Silva Apr. 22, 1919 1,679,873 Osbeck Aug. 7, 1928 2,676,829 Sterner Apr.27, 1954 FOREIGN PATENTS 232,717 Great Britain Apr. 30, 1925

